Did you trace the package to make sure that you hit the Send Mail task? If so, then check any error messages (while debugging) for that task. Also,...

SSRS doesn't have a built-in SUMPRODUCT function. However, you can easily make one. Just write a SumProduct function in VB (takes in two arrays, returns one number) and...

If you're I/O bound, start with the log files. Put them in separate filegroups, preferably on separate spindles.

If your tables are growing rapidly (e.g. transaction data) and...

It's likely that there will be a 1x1 mapping between Employee and voice Telephone numbers. So, keeping them in one simple table could be OK. Fax numbers may...

Assuming A and B have the same schema:

select * from A

except

select * from B

Just add to your where clause:

AND DateColumn <= '2015-01-01'

Why are the intervals in the desired output > 5 minutes?

+1 for surrogates. Keep the business keys out of fact tables. Resolve via Lookups during ETL

Here's a great article on the topic:

http://www.brentozar.com/archive/2012/07/identifying-correcting-sql-server-implicit-conversion/

I stopped relying on implicit conversion years ago. In fact, in all languages I write I try to adhere to the...

Sure, but Explicit is better than Implicit. SQL Server sometimes does not give you the implicit conversion...

Like this:

declare @pi nvarchar(10) = '3.14159E0'

select cast(@pi as float)

Where is column Datetime coming from?

You should post your DDL and some sample data as DML along with the results you want to see.

Try this expression in the Tablix Visibility tab:

=CountRows() = 0

"A waste of what?"

...a waste of time thinking about it.

Perhaps the question is more, "What is minimum number of rows threshold where a PK starts to pay off?"

Seems to me, if a table only ever has 1 row, a...